Personal area network
A personal area network (PAN) is a computer network used for communication among computer devices (including telephones and personal digital assistants) close to one person. The devices may or may not belong to the person in question. The reach of a PAN is typically a few meters. PANs can be used for communication among the personal devices themselves (intrapersonal communication), or for connecting to a higher level network and the Internet (an uplink).
A Bluetooth PAN is also called a piconet, and is composed of up to 8 active devices in a master-slave relationship (up to 255 devices can be connected in 'parked' mode). The first Bluetooth device in the piconet is the master, and all other devices are slaves that communicate with the master. A piconet typically has a range of 10 meters, although ranges of up to 100 meters can be reached under ideal circumstances.
Recent innovations in Bluetooth antennas have allowed these devices to far exceed the range which they were originally designed for. At DEFCON 12, with the right equipment a group of hackers known as "Flexilis" was able to achieve connectivity to bluetooth devices more than half a mile away. The type of antenna use was home made and yagi based. They named the antenna "The BlueSniper". This is a rifle stock with a scope and yagi antenna attached. A cable attaches the antenna to the Bluetooth card, which can be in a PDA or laptop computer. The laptop can be carried in a backpack with the cables connecting into the backpack, giving it the Ghostbusters look.